Answer: 21.75 (choice D)
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Explanation:
The mixed number 7 & 1/4 converts to the decimal form 7.25, since 1/4 = 0.25
The ratio 1:7.25 means that we'll multiply the smaller triangle's sides by the scale factor 7.25 to get the larger corresponding side
Meaning that the value of x is 3*7.25 = 21.75
This converts to the mixed number 21 & 3/4
